Marie Anne de Bourbon, Légitimée de France (2 October 1666 – 3 May 1739) was the eldest legitimised daughter (fille légitimée de France) of King Louis XIV of France and his mistress Louise de La Vallière. At the age of thirteen, she was married to Louis Armand de Bourbon, Prince of Conti and as such was the Princess of Conti by marriage. A great beauty and her father's favourite daughter, Marie Anne was widowed in 1685 aged 19. She never married again and had no children. Following her mother's retirement to a convent, Marie Anne continued to reside at her father's court and was later her mother's heiress. She later became the Duchess of La Vallière in her own right.

Born secretly at the Château de Vincennes outside Paris on 2 October 1666 while the court was in residence, Marie Anne was the eldest illegitimate child of King Louis XIV. Considered the king's most beautiful daughter, she would become his favourite female child. His favourite child, however, was her younger half-brother, Louis Auguste, Duke of Maine. She and her younger brother Louis de Bourbon (later Count of Vermandois) were put in the care of Madame Colbert, the wife of Finance Minister Jean-Baptiste Colbert. They were raised by Madame Colbert away from the intrigues of the Court.

The following year, Marie Anne was legitimised by her father on 14 May 1667. On the same day, her mother was given the titles of Duchess of La Vallière and of Vaujours with letters patent. Marie Anne would succeed to her mother's La Vallière title. During her youth, she was known as Mademoiselle de Blois, a style that was later granted to her younger half-sister, Françoise Marie de Bourbon, youngest daughter of the king by Madame de Montespan.

Marie Anne de Conti refusing the marriage proposal on behalf of Moulay Ismaïl, King of Morocco (French school of the 17th century)

On 16 January 1680, Marie Anne married her cousin, Louis Armand de Bourbon, Prince of Conti, in the chapel of the Château de Saint-Germain-en-Laye. He had fallen in love with her at first sight.[citation needed] Her dowry was one million livres. The marriage was the first between a Prince of the Blood and one of Louis XIV's legitimised daughters which caused a scandal at the time. After a disastrous wedding night, the marriage remained sterile and Marie Anne shocked the court when she openly stated that her husband was not good at making love.

In 1683, she lost her beloved brother the Count of Vermandois, who shared the same birthday with her. The young count had been exiled from court after being involved in a homosexual scandal involving their uncle's lover, the Chevalier de Lorraine, himself the long term lover of Marie Anne's uncle the Duke of Orléans. From all sources, Marie Anne was quite upset by her brother's death, while, according to contemporary accounts, the young man's parents did not even shed a tear.

In 1685, her husband contracted smallpox from Marie Anne. Although she recovered, he succumbed after five days. After his death, she was called Madame la Princesse Douairière, and also la Grande Princesse de Conti. She never remarried and even refused an offer of marriage from the Sultan of Morocco, Ismail Ibn Sharif preferring to be free.

During the five years of her marriage to the Prince of Conti, a Prince of the Blood, she was one of the most important ladies at her father's court. Her younger half sister Louise Françoise de Bourbon, the elder legitimised daughter of Louis XIV and Madame de Montespan, however, made a more important marriage in 1685 to Louis de Bourbon, Duke of Bourbon, who was the eldest son of the Prince of Condé and heir to the title. As the Conti line descended from the Condé's, the latter took precedence over the former and as such Marie Anne had to yield precedence to a sister seven years her junior. This matter of etiquette, so important at Versailles, led to friction between the two.

The situation of rank at Versailles grew more irritating to Marie Anne in 1692. In that year, Louise Françoise's full sister, Françoise Marie de Bourbon married the Duke of Chartres, Philippe d'Orléans, a petit-fils de France (grandson of France) by birth and heir to the House of Orléans. On her marriage, Françoise Marie assumed the rank of petite-fille de France, giving her precedence over both Marie Anne and Louise Françoise. In addition, she was given a dowry of 2 million livres, a much higher amount than what either of her sisters had received on her marriage. These developments greatly irritated both Marie Anne and Louise Françoise who were openly hostile to their younger sister who deliberately flaunted her position much to their annoyance.

In order to differentiate between them at court after the death of the various Princes of Conti, their widows were given the name of Douairière (dowager) and a number corresponding to the time of their widowhood, their full style thus being Madame la Princesse de Conti 'number' Douairière. Between 1727 and 1732, there were three widowed Princesses de Conti:

Marie Anne de Bourbon (1666–1739), the illegitimate daughter of Louis XIV and Louise de La Vallière; the wife of Louis Armand I de Bourbon, prince de Conti, became Madame la Princesse de Conti Première Douairière as she was the first to be widowed in 1685. The title went to husband's younger brother, François Louis, Prince of Conti.

From her staff at Versailles, Marie Anne introduced her older half brother, the Dauphin, to his second wife, Émilie de Choin. He married her morganatically after the death of his first wife, the unattractive Dauphine Marie Anne Victoire (1660–1690). One day, coming upon Marie Anne Victoire's sleeping form, Marie Anne commented that she was as ugly asleep as she was awake; whereupon the dauphine awoke and retorted that she did not "have the advantage of being a love child."

In 1710, Marie Anne's mother died in Paris at the Carmelite convent she had entered in 1674 under the name of Sister Louise of Mercy. Marie Anne thus acquired the title duchesse de La Vallière and inherited her mother's substantial fortune which had been accumulated over the past thirty-six years.

In 1713, the Princess of Conti bought the Hôtel de Lorges on the rue Saint-Augustin[1] in Paris, but did not start living there until 1715, and in 1716, the Château de Choisy. Both properties remained in her possession until her death. In 1718, she was presented by the Crown the Château de Champs-sur-Marne, which she later gave to her first cousin, the duc de La Vallière in order to settle some debts. Years later, it was leased for several years by Louis XV's mistress, Madame de Pompadour.

Marie Anne was renowned for her beauty, even at an older age. She was very close to her father, and got on very well with her older brother, Monseigneur, the Grand Dauphin, whom she often visited at his country estate, the château de Meudon. His death in 1711 left her quite distressed. It was at Meudon that Marie Anne met and fell in love with the young but very poor Count of Clermont-Chaste. He joined the court and benefited from his intimacy with Marie Anne. The couple exchanged love letters, but a swift exile was ordered for Clermont-Chaste when Louis XIV discovered the liaison (possibly from his daughter-in-law, Émilie de Choin).

Upon the death of Louis XIV on 1 September 1715, a regency was established and her brother-in-law, the Duke of Orléans was named as regent (1715–1723). In 1721, Marie Anne was made responsible for the education of Louis XV's future bride, the InfantaMariana Victoria of Spain, who arrived in France at the age of three. The young Infanta was nicknamed l'Infante-reine ('the Queen-Infanta'). However, because of the infanta's age, the marriage did not take place and the little girl was sent back to Spain four years later, in 1725, an event which caused friction between her father King Philip V of Spain and the youthful Louis XV.[citation needed] After the departure of the seven-year-old Infante-reine, Marie Anne then retired from court and spent her remaining years residing on her various estates.